The overall objective of the proposed research is the characterization, by means of a kinetic approach, of the mineralization of calcium phosphates and the inorganic and organic components of teeth such as whole and carious enamel and dentine, predentine, plaque, calculus, unerupted teeth, cementum and organic phases such collagen and elastin. The highly reproducible procedure of seeded growth in stable supersaturated solutions, developed in our laboratory, will be used and a wide range of calcium phosphate concentrations and pH typical of those in the mouth and at developing caries and calculus will be studied in order to provide information about the nature of the solid phases formed at various stages in the mineralization and demineralization reactions. In parallel with these studies, scanning electron microscopic investigations of the growing crystals will be made in order to relate crystal morphology to the kinetics of the growth process. The effects of commonly used anti caries and calculus agents as well as salivary constituents in modifying the course of the mineralization will be related to their behavior in the oral environment. Dissolution kinetic studies will also be made to identify the calcium phosphate phases. The dissolution of sound and white spot enamel will also be investigated using the well defined hydrodynamic conditions of the rotating disc in order to be able to construct a model capable of describing the observed rates of surface and of subsurface dissolution. Studies will also be made of the factors important in controlling the calcium phosphate nucleating ability of the organic substrates such as predentine, collagen and elastin. The information obtained from this proposed study will be helpful in the eventual elucidation of the mechanism of tooth mineralization, caries formation and the development of plaque and calculus.